Stormwater General Engineering Services Contract II
Coldwater, as a subconsultant, performed geomorphic assessments for multiple stream restoration projects for the Northeast Ohio Regional Sewer District (NEORSD). Accurate location and dimensioning of the banks, debris bars, scour pools and other features in the project areas is critical to evaluate and refine specific details of restoration and stabilization designs needed. Surveying of these features is often challenging.
Under the Stormwater General Engineering Services (GES) contract, Coldwater field assessments typically consisted of collecting stream cross-section measurements and data, identifying and measuring stream thalweg, performing pebble counts, locating bankfull and ordinary high water level indicators, and completing Bank Erosion Hazard Index (BEHI) calculations. Inspection of soil conditions and gradations were included as part of the field assessment as well. In support of the field data collected, desktop analysis such as drainage area delineations and watershed parameterization were also completed for each of the projects.
For each of the projects worked on under the GES contract, the results from the geomorphic field assessment were used to determine the Rosgen Level II stream classification using entrenchment ratios and width/depth ratios. Stream succession scenarios based on the exiting conditions stream classification were completed as part of the scopes of work. These succession scenarios were then used to aid in the development of proposed project alternatives and proposed stream design parameters for the design of the selected alternative.
Natural Channel Design
In-Stream Grade Control